In the multicoloured weaving and tufting of carpet, the various pile-warp yarns are often supplied from a bobbin creel to a device which, in accordance with the desired pattern, selects the pile-warp yarns or brings them into a position in which they produce the desired effect in the fabric.
Bobbin creels of this type can be very awkward both in terms of the area which they take up and in terms of the quantity and value of the yarn which they have in stock for carrying out the process.
A solution to limit both the necessary space and the amount of yarn in a yarn processing installation is described in EP 422 093. EP 422 093 describes a yarn storage system comprising a multiplicity of yarn buffer units arranged next to one another in the form of elongate tubes inside which yarn is stored. Each tube has an open entry side along which the yarn is supplied to the yarn store and an open output side through which the yarn is delivered from the store in the tube to the yarn processing device. In order to allow continuity in production by the yarn processing device, even during replenishing of the yarn stores, a yarn loader moves on the input side of the tubes, from tube to tube, to replenish the store of yarn in the tubes with the desired yarn for the continuation of the yarn processing process.
The replenishing takes place by connecting the newly supplied yarn to the most recently introduced part of the yarn in the yarn store in the tube, followed by supplying the new yarn by rotating the head of the yarn loader, thus laying in the tube successive windings which, in accordance with the activation of the yarn loader, can assume any desired shape: windings having a constant diameter, windings having a variable diameter, planetary windings, figures of 8, etc. The yarn loader can in this case be provided with a pressure disc which presses against the remaining store in order to attach the windings as uniformly as possible, to keep them compact and to prevent the windings from falling or becoming entangled. The newly laid windings push the yarn store further into the yarn storage tube. For the first filling of the yarn storage device, EP 422 093 provides a counter-disc to keep the first windings straight when no preceding yarn store is yet present against which to place the windings. Once the filling of the yarn storage tube has started up properly, this counter-disc is removed via the output side in order to make possible a supply of the yarn to the yarn processing device. From that moment, the only support to keep the windings straight is the friction between the windings and the tube wall.
At the output side, the yarn is extracted to supply it to the yarn processing device with the aim of removing each winding, one by one, from the yarn store.
However, this method gives rise to problems when windings fall into the yarn store and on drawing of the yarn from the output side several of the windings become entangled. The supply of entangled windings of this type to the yarn processing installation is disruptive and leads to yarn breakage and/or shutdown of the yarn processing installation. EP 0 422 093 offers no solution to this problem.
U.S. patent publication U.S. Pat. No. 3,345,702 describes a yarn storage system comprising a tube which serves as a buffer between two yarn processing machines. On one side of the tube, the yarns are supplied to provide a buffer and on the other side of the tube the yarns are delivered to the subsequent yarn processing machine. The yarn is placed in the yarn store as windings as a result of a movement of relative rotation between the tube and the supply.
In view of the fact that windings which have fallen over can cause entangling and as a result yarn breakage or machine shutdowns, U.S. Pat. No. 3,345,702 provides, as a solution for avoiding falling of the windings, a weight in the form of a ring or a disc which is introduced on the yarn delivery side and which presses on the winding diameter against the windings and wherein the yarn of the windings located closest to this ring or disc is drawn through an opening in the ring or disc in order to be supplied to the following yarn processing machine. In order to exert a press-on force on the windings, either the yarn storage tube is arranged obliquely, as a result of which a component of the weight of the ring or disc occurs as a press-on force, or a spring is placed between the tube end on the delivery side and the ring or disc, or both are used at the same time.
However, this device displays the following drawbacks:                in the case of a large yarn store (for example if the supply tube is filled over a long length), the risk increases that even on the input side windings will fall or assume a smaller diameter, as a result of which these windings will no longer be pressed on by the disc or ring if said disc or ring is located on the delivery side;        by drawing the yarns on the delivery side through an opening, windings which fall and fall over one another will become entangled more easily and cause yarn breakage, machine shutdowns or damage to the yarn storage system; this can be limited by making said opening larger, but has at the same time the consequence that more small or fallen-down windings extend through the opening.        
This risk increases when the hairiness of the yarns is greater, such as is for example the case with yarns used in Axminster weaving machines or tufting machines. A device of this type provides an inadequate solution to avoiding the falling-over and the entangling of yarn windings in a yarn storage system with successive yarn windings and still causes too much yarn breakage and too many machine shutdowns of the yarn processing machines.